Wipe test

Procedure for performing a wipe test:

• Use a moist filter paper (5x5 cm or similar) and wipe off the bench, equipment, handles, floors, etc. One filter paper for each area you are wiping off.
• Take a damp filter paper and wipe off an area that has not been used for radioactive work (blank sample).
• Place the filter papers in the scintillation glass and fill with a scintillation liquid.
• Count the samples in a scintillation counter (or a gamma counter)
• The work area is ready for use if the count from the wipe test is of the same order of magnitude as the blank sample. If the counts are higher than the blank sample, the work area must be washed again and a new wipe test must be completed. This is repeated until the counts are equal to the blank sample.
• The results from the wipe test must be stored.

When working with more energy-rich radiation sources such as P-32, the use of Geiger Müller will be sufficient.